Every year, more than 5 million central venous catheters (also called central lines) are placed by physicians. Central lines facilitate the delivery of medication and nutritional support to a patient, but can lead to a hospital acquired bloodstream infection. Associated symptoms of central line-associated bloodstream infections (CLABS Is) are sepsis, fever, and malaise. CLABS Is are a major concern for hospitals because they have been associated with increased morbidity and mortality, length of hospital stay, and cost.
Complications associated with low birth weight and premature infants make it necessary for many of these neonates to be admitted to the neonatal intensive care unit (NICU), where a majority of them receives umbilical catheters. Premature infants are particularly vulnerable to bloodstream infections due to their immature immune systems, poor skin integrity, exposure to numerous caregivers, placement in an environment that is conductive to bacterial colonization, and their subjection to repeated invasive procedures. Indeed, the rate of CLABSIs in these infants is far greater than that of adults.
Although umbilical catheterization is a necessary and life-saving procedure for many premature infants, outcomes from CLABSIs can be devastating. Catheter-related bloodstream infections in premature infants are associated with increased morbidity and mortality. Infants with CLABSIs have an increased risk for respiratory distress, severe intraventricular hemorrhage, periventricular leukomalacia, bronchopulmonary dysplasia, and death. CLABSIs are the most common cause of complications related to umbilical catheters, with approximately 5-15% of neonates with umbilical catheters developing CLABSIs. The rate is highest for the lowest birth weight infants, weighing under 1250 grams, who have umbilical catheter CLABSI rates of 15% or more.
Placement of an umbilical catheter is a delicate, multi-step process. First, the cord is elevated vertically and cut approximately one centimeter above the skin with a scalpel blade. Second, the closed tips of forceps are entered into the umbilical vein or artery in order to dilate the vessel. Third, the catheter is introduced into the vessel and advanced 4-5 centimeters. This step may be repeated if the catheter is not properly inserted. Fourth, blood is aspirated to verify catheter placement in the lumen and 0.5 mL of heparin is flushed to clear the lumen. Finally, the catheter is advanced to a predetermined length (based on height and weight of the neonate), attached to the umbilical stump with a suture, and the line is secured with a catheter bridge (sometimes made of surgical tape). Ideal placement of an umbilical venous catheter is at the junction of the inferior vena cava (IVC) and the right atrium of the heart.
Despite high complication risks, umbilical catheters remain the preferred route of catheterization in the NICU because they offer reliable access to the venous system with the necessary flow required to deliver these premature, and often sick, neonates medication, fluids, and parenteral nutrition. Umbilical catheters can also be used to monitor blood pressure and sample venous or arterial blood. With current technologies, physicians remove the umbilical catheter due to risk of CLABSI after approximately 6-8 days, even though there is still typically a need for central access. Indeed, a peripherally inserted central catheter (PICC) line or other form of central catheterization is usually placed in the neonate after UC removal.
Umbilical catheter CLABSIs are at least 5 times more common than central catheter associated bloodstream infections. One possible reason for this is that there is no device that is specific to the unique anatomy of the umbilical area or the unique demands of the neonate that can both protect the umbilical stump and stabilize the umbilical catheter(s).